Files
oceanbase/src/sql/engine/expr/ob_expr_normal.cpp
2023-04-27 11:11:24 +00:00

141 lines
4.6 KiB
C++

/**
* Copyright (c) 2021 OceanBase
* OceanBase CE is licensed under Mulan PubL v2.
* You can use this software according to the terms and conditions of the Mulan PubL v2.
* You may obtain a copy of Mulan PubL v2 at:
* http://license.coscl.org.cn/MulanPubL-2.0
* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
* See the Mulan PubL v2 for more details.
*/
#define USING_LOG_PREFIX SQL_ENG
#include "sql/engine/expr/ob_expr_normal.h"
#include "sql/engine/ob_exec_context.h"
namespace oceanbase
{
using namespace common;
namespace sql
{
int ObExprNormal::ObExprNormalCtx::initialize(ObEvalCtx &ctx, const ObExpr &expr)
{
int ret = OB_SUCCESS;
ObDatum &p1 = expr.locate_param_datum(ctx, 0);
ObDatum &p2 = expr.locate_param_datum(ctx, 1);
if (p1.is_null() || p2.is_null()) {
ret = OB_INVALID_ARGUMENT;
LOG_USER_ERROR(OB_INVALID_ARGUMENT, "normal function. first and second argument must be constant expression.");
} else {
double mean = p1.get_double();
double stddev = p2.get_double();
std::normal_distribution<double>::param_type param(mean, stddev);
normal_dist_.param(param);
}
return ret;
}
int ObExprNormal::ObExprNormalCtx::generate_next_value(int64_t seed, double &result)
{
normal_dist_.reset();
gen_.seed(static_cast<uint64_t>(seed));
result = normal_dist_(gen_);
return OB_SUCCESS;
}
ObExprNormal::ObExprNormal(common::ObIAllocator &alloc)
: ObFuncExprOperator(alloc, T_FUN_SYS_NORMAL, "normal", 3, NOT_VALID_FOR_GENERATED_COL, NOT_ROW_DIMENSION)
{
}
ObExprNormal::~ObExprNormal()
{
}
int ObExprNormal::calc_result_type3(ObExprResType &result_type,
ObExprResType &mean,
ObExprResType &stddev,
ObExprResType &rand_expr,
common::ObExprTypeCtx &type_ctx) const
{
UNUSED(type_ctx);
int ret = OB_SUCCESS;
mean.set_calc_type(ObDoubleType);
stddev.set_calc_type(ObDoubleType);
rand_expr.set_calc_type(ObIntType);
result_type.set_double();
return ret;
}
int ObExprNormal::eval_next_value(const ObExpr &expr,
ObEvalCtx &ctx,
ObDatum &res_datum)
{
int ret = OB_SUCCESS;
ObExprNormalCtx *normal_ctx = NULL;
uint64_t op_id = expr.expr_ctx_id_;
ObExecContext &exec_ctx = ctx.exec_ctx_;
if (OB_FAIL(expr.eval_param_value(ctx))) {
LOG_WARN("expr.eval_param_value failed", K(ret));
} else if (OB_ISNULL(normal_ctx = static_cast<ObExprNormalCtx *>(
exec_ctx.get_expr_op_ctx(op_id)))) {
if (OB_FAIL(exec_ctx.create_expr_op_ctx(op_id, normal_ctx))) {
LOG_WARN("failed to create operator ctx", K(ret), K(op_id));
} else if (OB_ISNULL(normal_ctx)) {
ret = OB_ALLOCATE_MEMORY_FAILED;
LOG_WARN("normal ctx is NULL", K(ret));
} else if (OB_FAIL(normal_ctx->initialize(ctx, expr))) {
LOG_WARN("fail init normal context", K(ret));
}
}
if (OB_SUCC(ret)) {
ObDatum &rand_val = expr.locate_param_datum(ctx, 2);
if (OB_UNLIKELY(rand_val.is_null())) {
res_datum.set_null();
} else {
int64_t seed = rand_val.get_int();
double next_value_res = 0.0;
if (OB_FAIL(normal_ctx->generate_next_value(seed, next_value_res))) {
LOG_WARN("fail generate next normal value", K(ret), K(seed));
} else {
res_datum.set_double(next_value_res);
}
}
}
return ret;
}
int ObExprNormal::cg_expr(ObExprCGCtx &expr_cg_ctx,
const ObRawExpr &raw_expr,
ObExpr &rt_expr) const
{
int ret = OB_SUCCESS;
UNUSED(expr_cg_ctx);
if (OB_UNLIKELY(3 != raw_expr.get_param_count())) {
ret = OB_INVALID_ARGUMENT;
LOG_WARN("invalid param count for in expr", K(ret));
} else if (OB_ISNULL(raw_expr.get_param_expr(0)) ||
OB_ISNULL(raw_expr.get_param_expr(1))) {
ret = OB_INVALID_ARGUMENT;
LOG_WARN("invalid null param expr", K(ret));
} else if (!raw_expr.get_param_expr(0)->is_const_expr()) {
ret = OB_INVALID_ARGUMENT;
LOG_USER_ERROR(OB_INVALID_ARGUMENT, "normal function's first argument. must be a constant expression.");
} else if (!raw_expr.get_param_expr(1)->is_const_expr()) {
ret = OB_INVALID_ARGUMENT;
LOG_USER_ERROR(OB_INVALID_ARGUMENT, "normal function's second argument. must be a constant expression.");
}
rt_expr.eval_func_ = ObExprNormal::eval_next_value;
return ret;
}
} /* namespace sql */
} /* namespace oceanbase */